Pixhawk "startup ok" sound?

Wiki has this sound example: plane.ardupilot.com/wiki/common-apm-board-leds (direct link: http://dev.ardupilot.com/wp-content/uploads/sites/6/2013/06/PX4_StartUpOk.wav)

My Pixhawk has this sound (notice the long single tone at the end): https://www.youtube.com/watch?v=-fYUpJf8kxg

What does the last sound mean (and if it’s normal, maybe update the wiki)?

startup tones seem fine and the long tone indicates it is arming. Since you still get flashing yellow at the end, check in mission planner what’s going as as it looks like a failsafe or pre arm check is not allowing you to arm automatically as plane firmware was meant to do.